Weld configuration

ABSTRACT

A float assembly according to an example of the present disclosure includes a guide extending in a first direction that has a stand-up and a shelf. A cover is oriented in a second direction substantially perpendicular to the first direction and welded to the stand-up at a weld joint. An undersurface of the cover abuts the shelf, and the abutment begins at a first distance in the second direction from the weld joint and ends at a second distance in the second direction from the weld joint.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/398,852, which was filed on Jan. 5, 2017, which claims priority toU.S. Provisional Application No. 62/275,508, which was filed on Jan. 6,2016 and is incorporated herein by reference.

BACKGROUND

A gas turbine engine typically includes a fan section, a compressorsection, a combustor section, and a turbine section. Air entering thecompressor section is compressed and delivered into the combustorsection where it is mixed with fuel and ignited to generate a high-speedexhaust gas flow. The high-speed exhaust gas flow expands through theturbine section to drive the compressor and the fan section. Thecompressor section typically includes low and high pressure compressors,and the turbine section includes low and high pressure turbines. Thecomponents may have associated fluid containers. As one example, acombustor may include an associated fuel container.

This disclosure relates to weld configurations. In some examples, weldconfigurations may be used in gas turbine engines, one example being afloat guide for a fuel container.

SUMMARY

A float assembly according to an example of the present disclosureincludes a guide extending in a first direction that has a stand-up anda shelf. A cover is oriented in a second direction substantiallyperpendicular to the first direction and welded to the stand-up at aweld joint. An undersurface of the cover abuts the shelf, and theabutment begins at a first distance in the second direction from theweld joint and ends at a second distance in the second direction fromthe weld joint.

In a further embodiment of any of the foregoing embodiments, the weldjoint extends in the first direction.

In a further embodiment of any of the foregoing embodiments, the guideand the cover form a cavity directly adjacent the weld joint.

In a further embodiment of any of the foregoing embodiments, the cavityis provided by the undersurface, the stand-up, and the shelf.

In a further embodiment of any of the foregoing embodiments, the cavityextends at least the first distance in the second direction.

In a further embodiment of any of the foregoing embodiments, the cavityis directly adjacent the abutment.

In a further embodiment of any of the foregoing embodiments, the weldjoint extends from the cavity to a surface of the cover opposite theunder surface.

A gas turbine engine according to an example of the present disclosureincludes a combustor and a fuel container in communication with thecombustor. The fuel container has a float assembly. The float assemblyincludes a guide extending in a first direction and having a stand-upand a shelf, and a cover oriented in a second direction substantiallyperpendicular to the first direction and welded to the stand-up at aweld joint. An undersurface of the cover abuts the shelf, and theabutment begins at a first distance in the second direction from theweld joint and ends at a second distance in the second direction fromthe weld joint.

In a further embodiment of any of the foregoing embodiments, the weldjoint extends in the first direction.

In a further embodiment of any of the foregoing embodiments, the guideand the cover form a cavity directly adjacent the weld joint.

In a further embodiment of any of the foregoing embodiments, the cavityis provided by the undersurface, the stand-up, and the shelf.

In a further embodiment of any of the foregoing embodiments, the cavityextends at least the first distance in the second direction.

In a further embodiment of any of the foregoing embodiments, the cavityis directly adjacent the abutment.

In a further embodiment of any of the foregoing embodiments, the weldjoint extends from the cavity to a surface of the cover opposite theunder surface.

A method for assembling a float assembly according to an example of thepresent disclosure includes welding a cover to a guide at a weld joint.The guide extends in a first direction and includes a stand-up and ashelf, and the cover is oriented in a second direction substantiallyperpendicular to the first direction. An undersurface of the cover abutsthe shelf, and the abutment begins at a first distance in the seconddirection from the weld joint and ends at a second distance in thesecond direction from the weld joint.

In a further embodiment of any of the foregoing embodiments, the weldjoint extends in the first direction.

These and other features may be best understood from the followingdrawings and specification.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically shows an embodiment of a gas turbine engine.

FIG. 2 shows a prior art weld configuration.

FIG. 3 schematically shows an example float assembly in a fluidcontainer.

FIG. 4 is a cross sectional view of a prior art float assembly weldconfiguration.

FIG. 5 shows an example weld configuration.

FIG. 6 shows another example weld configuration.

FIG. 7 shows another example weld configuration.

DETAILED DESCRIPTION

FIG. 1 schematically illustrates a gas turbine engine 20. The gasturbine engine 20 is disclosed herein as a two-spool turbofan thatgenerally incorporates a fan section 22, a compressor section 24, acombustor section 26 and a turbine section 28. Alternative engines mightinclude an augmentor section (not shown) among other systems orfeatures. The fan section 22 drives air along a bypass flow path B in abypass duct defined within a nacelle 15, while the compressor section 24drives air along a core flow path C for compression and communicationinto the combustor section 26 then expansion through the turbine section28. Although depicted as a two-spool turbofan gas turbine engine in thedisclosed non-limiting embodiment, it should be understood that theconcepts described herein are not limited to use with two-spoolturbofans as the teachings may be applied to other types of turbineengines including three-spool architectures.

The exemplary engine 20 generally includes a low speed spool 30 and ahigh speed spool 32 mounted for rotation about an engine centrallongitudinal axis A relative to an engine static structure 36 viaseveral bearing systems 38. It should be understood that various bearingsystems 38 at various locations may alternatively or additionally beprovided, and the location of bearing systems 38 may be varied asappropriate to the application.

The low speed spool 30 generally includes an inner shaft 40 thatinterconnects a fan 42, a first (or low) pressure compressor 44 and afirst (or low) pressure turbine 46. The inner shaft 40 is connected tothe fan 42 through a speed change mechanism, which in exemplary gasturbine engine 20 is illustrated as a geared architecture 48 to drivethe fan 42 at a lower speed than the low speed spool 30. The high speedspool 32 includes an outer shaft 50 that interconnects a second (orhigh) pressure compressor 52 and a second (or high) pressure turbine 54.A combustor 56 is arranged in exemplary gas turbine 20 between the highpressure compressor 52 and the high pressure turbine 54. A mid-turbineframe 57 of the engine static structure 36 is arranged generally betweenthe high pressure turbine 54 and the low pressure turbine 46. Themid-turbine frame 57 further supports bearing systems 38 in the turbinesection 28. The inner shaft 40 and the outer shaft 50 are concentric androtate via bearing systems 38 about the engine central longitudinal axisA which is collinear with their longitudinal axes.

The core airflow is compressed by the low pressure compressor 44 thenthe high pressure compressor 52, mixed and burned with fuel in thecombustor 56, then expanded over the high pressure turbine 54 and lowpressure turbine 46. The mid-turbine frame 57 includes airfoils 59 whichare in the core airflow path C. The turbines 46, 54 rotationally drivethe respective low speed spool 30 and high speed spool 32 in response tothe expansion. It will be appreciated that each of the positions of thefan section 22, compressor section 24, combustor section 26, turbinesection 28, and fan drive gear system 48 may be varied. For example,gear system 48 may be located aft of combustor section 26 or even aft ofturbine section 28, and fan section 22 may be positioned forward or aftof the location of gear system 48.

The engine 20 in one example is a high-bypass geared aircraft engine. Ina further example, the engine 20 bypass ratio is greater than about six(6), with an example embodiment being greater than about ten (10), thegeared architecture 48 is an epicyclic gear train, such as a planetarygear system or other gear system, with a gear reduction ratio of greaterthan about 2.3 and the low pressure turbine 46 has a pressure ratio thatis greater than about five. In one disclosed embodiment, the engine 20bypass ratio is greater than about ten (10:1), the fan diameter issignificantly larger than that of the low pressure compressor 44, andthe low pressure turbine 46 has a pressure ratio that is greater thanabout five 5:1. Low pressure turbine 46 pressure ratio is pressuremeasured prior to inlet of low pressure turbine 46 as related to thepressure at the outlet of the low pressure turbine 46 prior to anexhaust nozzle. The geared architecture 48 may be an epicycle geartrain, such as a planetary gear system or other gear system, with a gearreduction ratio of greater than about 2.3:1. It should be understood,however, that the above parameters are only exemplary of one embodimentof a geared architecture engine and that the present invention isapplicable to other gas turbine engines including direct driveturbofans.

A significant amount of thrust is provided by the bypass flow B due tothe high bypass ratio. The fan section 22 of the engine 20 is designedfor a particular flight condition—typically cruise at about 0.8 Mach andabout 35,000 feet (10,668 meters). The flight condition of 0.8 Mach and35,000 ft (10,668 meters), with the engine at its best fuelconsumption—also known as “bucket cruise Thrust Specific FuelConsumption (‘TSFC’)”—is the industry standard parameter of lbm of fuelbeing burned divided by lbf of thrust the engine produces at thatminimum point. “Low fan pressure ratio” is the pressure ratio across thefan blade alone, without a Fan Exit Guide Vane (“FEGV”) system. The lowfan pressure ratio as disclosed herein according to one non-limitingembodiment is less than about 1.45. “Low corrected fan tip speed” is theactual fan tip speed in ft/sec divided by an industry standardtemperature correction of [(Tram ° R)/(518.7° R)]°^(0.5). The “Lowcorrected fan tip speed” as disclosed herein according to onenon-limiting embodiment is less than about 1150 ft/second (350.5meters/second).

FIG. 2 illustrates a prior art weld configuration including a member 80extending in a first direction supporting a member 82 extending in asecond direction substantially perpendicular to the first direction. Themember 82 and the member 80 are welded together at the weld joint 84extending in the first direction. The upper end of the member 80includes a stand-up 86 extending in the first direction and a shelf 88extending in the second direction. The undersurface 90 of the member 82interfaces with the upper surface 92 of the shelf 88 of the member 80from point P at the weld joint 84 to point Q. While adequate for manyapplications, it may be desired in some weld configurations to havereduced stress concentration on the weld's root or backside.

As illustrated schematically in FIG. 3, the combustor 56 is incommunication with a fluid container 200. The fluid container 200includes a body of fluid 203, one example fluid 203 being fuel, and afloat 72 within the body of fluid 203. The float 72 is coupled to poppetvalve 202 for activating a valve or switch 206 that controls fluid flowin and/or out of the container 200.

FIG. 4 illustrates, as one example of the prior art weld configurationin FIG. 2, a prior art float 72 in cross section. The float 72 has oneor more guides 80 extending in a first direction and supporting a cover82 oriented in a second direction substantially perpendicular to thefirst direction. The cover 82 and the guide 80 are welded together atthe weld joint 84 extending in the first direction. The upper end of theguide 80 includes a stand-up 86 extending in the first direction and ashelf 88 extending in the second direction. The undersurface 90 of thecover 82 interfaces with the upper surface 92 of the shelf 88 of theguide 80 from point P at the weld joint 84 to point Q.

The guides 80 provide openings 94 in the float 72 for receiving thefluid 203 (see FIG. 3) and fluidly isolate the openings 94 from cavities96. The cavities 96 may be filled with air or may be a vacuum, forexample, allowing the float 72 to float in the fluid 203.

FIG. 5 illustrates an example configuration for a guide 80 extending ina first direction and cover 82 oriented in a second directionsubstantially perpendicular to the first direction. The guide 80includes, at its upper end, a stand-up 100 extending in the firstdirection. The guide further includes a shelf 102 having a portion 103extending in the second direction and a portion 104 extending in thefirst direction from the portion 103.

The cover 82 is welded to the stand-up 100 of guide 80 at a weld joint106 extending in the first direction. The undersurface 108 of the cover82 abuts the upper surface 110 of the portion 104 of the guide 80. Theabutment begins at point A and ends at point B, and points A and B areboth spaced in the second direction from the weld joint 106. Theabutment of the undersurface 108 and the upper surface 110 is spaced inthe second direction from the weld joint 106, such that a cavity 112 isformed underneath the undersurface 108 and between the stand-up 100 andthe portion 104 of the shelf 102. The example configuration of FIG. 5results in a reduced stress concentration on the weld's backside.

As shown, the width w of the cavity 112 on the second direction issubstantially the same as the thickness t of the guide 80. As oneexample, the width w is 1-1.5 times the thickness t. The cavity 112 maycapture weld spatter.

FIG. 6 illustrates a second example configuration of a guide 80extending in a first direction and a cover 82 oriented in a seconddirection substantially perpendicular to the first direction. The upperend of the guide 80 includes a stand-up 120 having a section 122extending in the first direction and a section 124 extending in thesecond direction from the section 122. The guide further includes ashelf 126 extending in the second direction.

The cover 82 is welded to the section 124 of the stand-up 120 of theguide 80 at a weld joint 128 extending in the first direction. Theundersurface 130 of the cover 82 abuts the upper surface 132 of theshelf 126 of the guide 80, and the abutment is spaced in the seconddirection and in the first direction from the weld joint 128. Theabutment begins at point C and ends at point D, and points C and D areboth spaced in the second direction from the weld joint 128. Theundersurface 130 of the cover 82 has a tapered portion 134 that tapersas it approaches the weld joint 128. The section 124 and the section 122of the stand-up 120, the tapered portion 134, and the upper surface 132form a cavity 136 below the weld joint 128. A portion of the weld ofweld joint 128 may extend into the cavity 136. The example configurationof FIG. 6 results in a reduced stress concentration on the weld'sbackside.

FIG. 7 illustrates a third example configuration of a guide 80 extendingin a first direction and a cover 82 oriented in a second directionsubstantially perpendicular to the first direction. The upper end of theguide 80 includes a stand-up 140 having a portion 142 extending in thefirst direction and a portion 144 extending in the second direction fromthe portion 142. The upper end of the guide 80 further includes a shelf146 having a portion 147 extending in the second direction and a portion149 extending diagonally in both the first and second directions.

The cover 82 is welded to the portion 144 of the stand-up 140 of guide80 at a weld joint 148 extending in the first direction. An undersurface150 of the cover 82 abuts an upper surface 152 of the shelf 146. Theabutment begins at point E and ends at point F, and both points E and Fare spaced in the second direction from the weld joint 148. Theundersurface 150 tapers 154 as it approaches the weld joint 148 to forma concave surface 156. The concave surface 156, the portion 144 of theguide 80, the portion 142 of the guide 80, and the portion 149 of theshelf 146 form a cavity 160 underneath the weld joint 148. The exampleconfiguration of FIG. 7 results in a reduced stress concentration on theweld's backside.

As one example, the example weld configurations described herein areprovided by electron beam welding. Of course, other types of welding arecontemplated.

Although the examples disclosed are weld configurations for a floatassembly, one of ordinary skill in the art having the benefit of thisdisclosure would recognize that that the disclosed weld configurationsare not limited to such applications.

It should be understood that relative positional terms such as“forward,” “aft,” “upper,” “lower,” “above,” “below,” “upper surface,”“undersurface,” and the like are with reference to the orientation shownin the figures and should not be considered otherwise limiting. Termssuch as “generally,” “substantially,” and “about” are not intended to beboundaryless terms, and should be interpreted consistently with the wayone skilled in the art would interpret those terms.

The foregoing description is exemplary rather than defined by thelimitations within. Many modifications and variations of the presentinvention are possible in light of the above teachings. The disclosedembodiments of this invention have been disclosed, however, one ofordinary skill in the art would recognize that certain modificationswould come within the scope of this invention. It is, therefore, to beunderstood that within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described. For thatreason the following claims should be studied to determine the truescope and content of this invention.

What is claimed is:
 1. A float assembly comprising: a fuel float,comprising: a guide extending in a first direction and having a stand-upand a shelf; and a cover oriented in a second direction substantiallyperpendicular to the first direction and welded to the stand-up at aweld joint, wherein an undersurface of the cover abuts the shelf at anabutment, and the abutment begins at a first distance in the seconddirection from the weld joint and ends at a second distance in thesecond direction from the weld joint.
 2. The float assembly as recitedin claim 1, wherein the weld joint extends in the first direction. 3.The float assembly as recited in claim 1, wherein the guide and thecover form a cavity directly adjacent the weld joint.
 4. The floatassembly as recited in claim 3, wherein the cavity is bound by theundersurface, the stand-up, and the shelf.
 5. The float assembly asrecited in claim 4, wherein the cavity extends at least the firstdistance in the second direction.
 6. The float assembly as recited inclaim 3, wherein the cavity is directly adjacent the abutment.
 7. Thefloat assembly as recited in claim 3, wherein the weld joint extendsfrom the cavity to a surface of the cover opposite the under surface. 8.The float assembly as recited in claim 1, wherein the guide and thecover provide at least one interior cavity, the guide provides anopening in the float assembly, and the guide fluidly isolates theopening from the interior cavity.
 9. The float assembly as recited inclaim 4, wherein the cover tapers as it extends toward the weld joint toform a tapered portion tapering as it extends away from the shelf, andthe cavity is bound by the undersurface at the tapered portion.
 10. Agas turbine engine, comprising: a combustor; a fuel container incommunication with the combustor, the fuel container including a floatassembly within a body of fuel in the fuel container, wherein the floatassembly comprises: a guide extending in a first direction and having astand-up and a shelf; and a cover oriented in a second directionsubstantially perpendicular to the first direction and welded to thestand-up at a weld joint, wherein an undersurface of the cover abuts theshelf at an abutment, and the abutment begins at a first distance in thesecond direction from the weld joint and ends at a second distance inthe second direction from the weld joint.
 11. The gas turbine engine asrecited in claim 10, wherein the weld joint extends in the firstdirection.
 12. The gas turbine engine as recited in claim 10, whereinthe guide and the cover form a cavity directly adjacent the weld joint.13. The gas turbine engine as recited in claim 12, wherein the cavity isprovided by the undersurface, the stand-up, and the shelf.
 14. The gasturbine engine as recited in claim 13, wherein the cavity extends atleast the first distance in the second direction.
 15. The gas turbineengine as recited in claim 12, wherein the cavity is directly adjacentthe abutment.
 16. The float assembly as recited in claim 12, wherein theweld joint extends from the cavity to a surface of the cover oppositethe under surface.
 17. The gas turbine engine as recited in claim 10,wherein the float is coupled to a poppet valve for activating a switchthat controls fluid flow into or out of the container.